The side-parts of diapers are normally fastened together with the aid of fastener tabs which are firmly anchored to one side-part of the diaper and which when donning the diaper are fastened to the other side-part of the diaper with the aid of a releasable and refastenable type of adhesive. The side-part onto which the fastener tab is fastened when putting on the diaper may be reinforced in different ways, to enable the fastener means to be released and refastened repeatedly without damaging the diaper casing sheet. One problem with the use of adhesive tape is that contaminants, such as baby talcum, are liable to stick to the adhesive and therewith impair its adhesiveness. Furthermore, many users lack a clear indication as to where the fastener tabs shall be fastened in order to obtain a suitable tight fit around the waist of the wearer. There is therefore a need for mechanical fasteners for fastening the side-parts of diapers together. One such mechanical fastener means is known from U.S. Pat. No. 4,701,170, which describes a diaper whose side-parts are fastened together with the aid of mutually coacting resilient hook devices.